A silica‐supported monomeric alkylaluminum co‐catalyst was prepared via surface organometallic chemistry by contacting tris(neopentyl)aluminum and partially dehydroxylated silica. This system, fully characterized by solid‐state ²⁷Al NMR spectroscopy augmented by computational studies, efficiently activates (ⁿBu₃P)₂NiCl₂ towards dimerization of ethene, demonstrating comparable activity to previously reported dimeric diethylaluminum chloride supported on silica. Three types of aluminum surface species have been identified: monografted tetracoordinated Al species as well as two types of bisgrafted Al species—tetra‐ and pentacoordinated. Of them, only the monografted Al species is proposed to be able to activate the (ⁿBu₃P)₂NiCl₂ complex and generate the active cationic species.

中文翻译：

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硅接枝的三（新戊基）铝：一种高效的镍催化乙烯二聚的单体铝固体助催化剂。

通过使三（新戊基）铝与部分脱羟基的二氧化硅接触，通过表面有机金属化学制备了一种二氧化硅负载的单体烷基铝助催化剂。该系统完全以固态²⁷ Al NMR光谱为特征，并通过计算研究加以增强，可有效激活（ⁿ Bu ₃ P）₂ NiCl ₂乙烯的二聚反应，证明其活性与先前报道的负载在二氧化硅上的二聚二乙基氯化铝相当。现已鉴定出三种类型的铝表面物种：单接枝的四配位Al物种和两种双接枝的Al物种-四配位和五配位。在它们之中，仅提出单接枝的Al物种能够激活（ⁿ Bu ₃ P）₂ NiCl ₂络合物并产生活性阳离子物种。